No Effect of Serotoninergic Gene Variants on Response to Interpersonal Counseling and Antidepressants in Major Depression

Abstract

ObjectiveGene variants within the serotonin pathway have been associated with major depressive disorder (MDD) treatment outcomes, however a possible different modulation on pharmacological or psychological treatments has never been investigated.MethodsOne hundred sixty MDD patients were partially randomized to either inter-personal counseling (IPC) or antidepressants. The primary outcome was remission at week 8. Five serotonergic polymorphisms were investigated (COMT rs4680, HTR1A rs6295, HTR2A rs2224721, HTR2A rs7997012 and SLC6A4 rs421417).ResultsIPC (n=43) and antidepressant (n=117) treated patients did not show any difference in remission rates at week 8 (corrected for baseline severity, age and center). None of the studied gene variants impacted on response and remission rates at week 8 neither in the IPC nor in the antidepressant group. An analysis of the whole sample showed a trend of association between rs7997012 AA genotype and a better treatment outcome.ConclusionOur study confirms that IPC is an effective psychological intervention comparable to antidepressants in mild-moderate MDD. Polymorphisms related to the serotonin system did not exert a major effect on clinical outcomes in none of the treatment groups.

Serotonin Transporter Gene: A New Polymorphism May Affect Response to Antidepressant Treatments in Major Depressive Disorder

“…The majority of patients were treated with SSRIs (80.4 %), and further clinical data have been reported in a previous paper [48]. Non-completers (12.74 %) did not show any difference in age, sex, and baseline severity when compared with the 8-week completers [48]. As previously reported [48], no difference was observed in clinical outcomes between the two treatment groups (Table 1).…”

“…As previously reported in this sample [48], IPC, as well as antidepressants, are effective in the treatment of mild to moderate MDD. The SLC6A4 rs8076005 AA genotype and A allele were associated with response in the antidepressant group, with consistent trends in the whole sample (Tables 2 and 3).…”

“…Non-completers (12.74 %) did not show any difference in age, sex, and baseline severity when compared with the 8-week completers [48]. As previously reported [48], no difference was observed in clinical outcomes between the two treatment groups (Table 1). In the IPC group, the number of remitters was slightly higher than that of responders because the IPC group had lower baseline severity than the antidepressant group.…”

“…Inclusion and exclusion criteria have been detailed elsewhere [48]. Eligible patients were divided into interpersonal counseling (IPC, a type of brief psychotherapy derived from interpersonal psychotherapy [IPT] [49][50][51]) or pharmacological antidepressant treatment [52] groups.…”

“…Eligible patients were divided into interpersonal counseling (IPC, a type of brief psychotherapy derived from interpersonal psychotherapy [IPT] [49][50][51]) or pharmacological antidepressant treatment [52] groups. Subjects were collected in three centers (Neuroscience Department, Turin University; Department of Health Sciences, University of Pavia; and Institute of Psychiatry, Bologna University), as previously reported [48]. All patients recruited at Bologna University were treated with antidepressant drugs.…”